Thread-controller for sewing machines



Oct. 5, 1937. A. B. CLAYTON THREAD CONTROLLER FOR SEW ING MACHINES Filed June 23, 1934 3 Sheets-Sheet 1 fidrewB. Cla yian Oct. 5, 1937. A. B. CLAYTON 2,095,212 7 v THREAD COII'I'ROLILER FOR SEWING MACHI NES Filed June 25, 1934 a Sheets-Sheet 2 Andrew B. Clayion C'WHW865 I I Oct. 5, 1937. A. B. CLAYTON THREAD CONTROLLER FOR SEWING MACHINES Filed June :23, 1934 s Shee t s-Shee'c 3 Andre-11x5. Cld yion Patented a. 5, 1937 UNITED STATES PATENT OFFICE THREAD-CONTROLLER FOR SEWING MACHINES Application June 23,1934, Serial No. 732,041

2 Claims. (Cl. 112248) This invention relates to sewing machine thread-controllers more particularly of the rotary type commonly used to control the looperthread of a chain-stitch sewing machine.

The inventionhas for an object to provide a rotary thread-controller of simplified and improved construction, which has an easy action on the looper-thread and whichwill not catch and wind looper-thread from the source of supply, in case of thread-breakage. Another object of the inventionis to provide a rotary threadcontroller which may be quickly and easily threaded up, or re-threaded with a minimum loss of timein case of thread-breakage. A further object of the invention is to provide a threadcontroller which adequately guards the looperthread from becoming fouled by abnormal contact with adjacent moving parts or by oil from adjacent working bearings.

With the above and other objects in view, as will hereinafter appear, the invention comprises the devices, combinations, and arrangements of parts hereinafter set forth and illustrated in the accompanying drawings of a preferred embodiment of the invention, from which the several features'of theinvention and the advantages attained thereby will be readily understood by those skilled in the art.

, In the accompanying drawings, Fig. 1 is a top plan view of the cloth-plate and bed of a multipleneedle double-thread chain-stitch sewing machine embodying the invention. Fig. 2 is a vertical section on the line 2-2, Fig. 1. Fig. 3 is a vertical section at right angles to the line 2-2, Fig. 1.

'35 Fig. 4 is a fragmentary elevational view of a leadinthread-guide looking in the direction of the arrows 44, Fig. 1. Fig. 5 is a bottom plan view of the thread-controller guard-plate and asso elated thread-guides. Fig. 6 is a perspective view of the upper side of the guard-plate and associated thread-guides, and Fig. 7 is an enlarged sectional view on'the line l-'l, Fig. 1.

' The-invention isdisclosed as embodied in a double-thread chain-stitch sewing machine of the type represented in United States Patents Nos.

1,100,124, of June 16,1914, and 1,569,912, of Jan- 19, 1926. Such a machine has the usual bed ithread-carrying loopers 5 which latter are actuated in the usual manner, as shown in said patcuts, by the inclined crank 6 on the rotary mainshaft 1 journale d above the bed I and below the cloth-plate 3 in suitable bearings including the bearing 8 in the bearing pedestal 9.

The cloth-plate 3 carries the usual throat-plate to having the needle-holes H and clearance slots I2 for the feed-dog l3 which cooperates with the presser-foot M to feed the Work and is carried by the usual feed-bars l3 The main-shaft I. car ries the usual feed-eccentric l3 and feed-lift eccentric l3". 10

To control the looper thread or threads, there is mounted on the shaft 1, close to the bearing 8, a rotary thread-cam I 5 having on that face thereof adjacent the bearing 8 an oil-sling Hi. It will be observed that the thread-cam I5 is a 15 single-disk cam, that is, it has no peripheral g-roove therein such as has heretofore been commonly provided to receive'the usual slotted cast-v ofi and which groove has been a source of annoyance due to its tendency to wind looper- 20 thread from the supply in case of thread-breakage.

Mounted on the bearing pedestal 9 is a bracket l1 to which is screwed the guard-plate l8 having a slot l9 therein through which the thread-cam 25 I5 projects. The guard-plate I8 is thus mounted above and parallel to the shaft 1 and below the cloth-plate 3 which has an opening 3' therein exposing the guard-plate; such opening being normally closed. by the removable cover-plate .3". 30 The guard-plate l8 also covers the feed-eccentric l3" and prevents the looper-thread from being fouled thereby.

Adjustably secured by screws 20 on top of the r guard-plate I8 at opposite sides of the plane of 30 the thread-cam [5 are the thread-guides 2| each of which isin the form of a hook having a forwardly opening thread-receiving throat 22, Fig. 6, leading to the bottom or reverse bend 23 which guides the looper-thread. 40

Spaced above and parallel to the guard-plate I8 is the thread-detainer 24 in the form oi. a U-shaped wire loop embracing the thread-cam I5 and secured by its legs to the plate l8 by the clamp-screw 25 and double grooved clamping washer 26, Fig. 7;] the thread-detainer being held spaced above the guard-plate by the supporting spacing washer 21. The free end 24' of'the thread-detainer is inclined upwardly adjacent the open throats 22 of the thread-guides 2| to facili tate the lateral introduction of the looper-thread simultaneously to thethread-guides 2| and under the thread-detainer 24, in threading up the machine. The legs of the thread-detainer 24 are substantially parallel to the cam IS. The guardplate l8 and thread-detainer 24 constitute threaddetaining means the spaced surfaces of which define a horizontal thread-passageway which extends in opposite directions entirely beyond the periphery of the cam l5. Hence the cam l may be turned in either direction without dislodging the thread from such passageway.

Also mounted on'the guard-plate l8 at opposite sides of the plane of the thread-cam [5 are the similar angle-plates 28 having therein the vertical thread-guiding slots 29 and thread-re taining spring wires 30 permitting lateral introduction of the looper-threads, or in other words providing a self-threading construction.

There is preferably secured to the under side of the guard-plate IS a thin fibre strip 3| the edge 32 of which preferably contacts or wipes against the side of the thread-cam l5 nearer the source of thread-supply and prevents the looperthread from being carried to and wound upon the thread-cam hub IS in case of thread-breakage.

There is also secured to the under side of the guard-plate l8 an inverted U-shaped oil-guard 33 having an inwardly extending flange 34 which overhangs the oil-sling I6, as shown in Fig. 3.

The cloth-plate 3 is provided with a threadslot 35 extending from the opening 3 toward the rearward side of the standard 2 where the thread-tension devices (not shown) are commonly located. The thread-slot 35 is bridged under by an integrally cast loop 31, Fig. 4, which serves as a cross-brace as well as a lead-in threadguide. A guard-flange 38 screwed to the bed I is formed with' a large threading hole 39 connected by a slot 40 to the slot 35.

To thread the loopers, the ends of the looperthreads from the tension-devices are first insorted through the large hole 39 in the guardplate and then drawn forwardly above the clothplate 3 to a point beyond the thread-controller cam 15. The threads are then passed laterally of themselves and downwardly through the slot 35 and under the retaining wire 30 into the respective guide-slots 29 in the guide-plates 28.

The threads are then grasped between the guideplates 28 and pulled toward the operator and passed under the free ends of the guides 2| and detainer 24. The loopers 5 are then threaded in the usual manner. when the machine is started,

the thread between the guides 28 is carried .by the cam l5 to the bottoms 23 of the throats 22 in the guides 2| and under the detainer 24. The cam i5 is shaped to take-up the pay-out looperthread as required by the loopers and prevent the formation of undue slack in the looper-thread at any point in the stitch-forming cycle. The thread-loop engaged by the cam- 15 is confined to a substantially horizontal movement by the guard-plate l8 and overlying detainer 24. The guard-plate l8 may act as a stripper to prevent the cam I5 from carrying the engaged threadloop around the shaft I.

The bearing 8, as well as various other bearings of the machine, is lubricated by an oil-pipe 4| leading from an oil-main 42 to the horizontal oil-duct 43 extending under the bushing 8 and in communication with the oil-hole 44 leading upwardiy through the bushing 8 to the bearing surfaces. r

The invention is not to be understood as limited to the details of construction and relative arrangements of parts shown and described in this detailed disclosure of a preferred embodiment of the invention. It is obvious that various modifications may be made by one skilled in the art within the spirit and scope of the invention.

Having thus set forth the nature of the invention, what I claim herein is 1. A sewing machine having a bed, a standard and a cloth-plate raised above said bed and formed with an opening therein and a threadslot extending from said opening to the edge of said cloth-plate adjacent said standard, a threadguide carried by said cloth-plate and bridging under said slot adjacent said standard, a rotary shaft journaled below said cloth-plate, a looper actuated by said shaft, a rotary looper-thread controller cam mounted on said shaft below the opening in said cloth-plate, thread-guides oooperating with said thread-controller cam, and a removable cover for said opening.

2. In a sewing machine, a bed having a bearing pedestal, a rotary shaft having a bearing in said pedestal, a rotary thread-controller cam mounted on said shaft and formed with a hub having an oil-sling adjacent one end of said bearing, and an inverted U-shaped oil-guard embracing said oil-sling. I

. ANDREW B. CLAYTON. 

